122 Carat Blue Fetches $27 Million, Doesn’t Set Record

The 122.52 ct. blue diamond rough found in June—one of the most significant gem finds in recent years—has been sold for $27.6 million, far below the record price some were expecting.

That price works out to a $225,269 a carat.

Petra Diamonds, which found the gem at its Cullinan mine in South Africa, sold it to a partnership comprising an anonymous polisher, which owns 85 percent, and Petra, which owns the rest.

Given the sky-high expectations, one local newspaper dubbed it “a bit of a bargain” for its buyer. When its discovery was first announced, some analysts predicted it could go for close to $40 million, which would set a new benchmark for the highest recorded price for a piece of rough. (The current record is held by Petra, which sold a 507 ct. white stone for $35.3 million in February 2010.)

Spokesperson Cornelia Grant says the stone was tendered in South Africa, and Petra considered both partnership opportunities as well as straightforward bids.

“The agreement announced today offered the best value to Petra,” she says. “Not only do we record a significant sales value for the rough stone, but we also share in the value of the entire polished yield.”

The miner has gone the partnership route before, when it teamed up with Sotheby’s to cut and polish a 26 ct. blue. That was eventually sold at auction as the 7 ct. Star of Josephine, which sold for $9.5 million.

Grant declined to comment on its clarity or what size polished might result from this stone.

Like the blue? Here’s another view.

But Thomas Gelb, education director for the Natural Color Diamond Association, feels it will result in a sizable stone, possibly even beating the 45 ct. Hope, which is also blue. (The blue Idol’s Eye weighs 70 cts.)

“Given that it is from the Cullinan mine it is very likely a type IIb boron-rich diamond,” he says. “Type IIb diamonds are generally less likely to cleave or fracture during cutting and very frequently have few internal inclusions. So this may well result in a very large and important natural color blue diamond.”